Biomimetic Olfactory System Based on Temperature-Modulated Sensor Arrays for Detecting Trace Volatile Semiochemicals of Plants.

Volatile aroma compounds (VACs) are key semiochemicals induced and released by plants under biotic and abiotic stresses. Therefore, it is of great significance for detecting VACs to evaluate the growth environment information and physiological markers of plants. However, real-time and on-site monitoring of VACs at the current stage remains a challenge due to their complex species and trace concentrations. Here, we report an ultrasensitive VAC sensor based on Ru-nanocluster-anchored ZnO nanodisks, for which the corresponding limit of detection for VACs can reach as low as 10 ppb. By constructing temperature-modulated 4 × 4 VAC sensor arrays and integrating artificial intelligence algorithms, we demonstrate simultaneous identification of 10 VAC species and concentrations with 98% accuracy and high fidelity. Furthermore, a portable biomimetic olfactory e-nose based on temperature-modulated sensor arrays was developed to realize the on-site detection of VACs released from tea plants induced by Ectropis obliqua. This work not only provides a design strategy for ultrasensitive VAC sensors but also establishes a scalable platform for real-time plant health monitoring and early warning of biotic and abiotic stresses.